<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\Common\Cache;

use Memcache;

/**
 * Memcache cache driver.
 *
 * @license http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link    www.doctrine-project.org
 * @since   2.0
 * @version $Revision: 3938 $
 * @author  Benjamin Eberlei <kontakt@beberlei.de>
 * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>
 * @author  Jonathan Wage <jonwage@gmail.com>
 * @author  Roman Borschel <roman@code-factory.org>
 * @author  David Abdemoulaie <dave@hobodave.com>
 */
class MemcacheCache extends AbstractCache {
	/**
	 * @var Memcache
	 */
	private $_memcache;
	
	/**
	 * Sets the memcache instance to use.
	 *
	 * @param Memcache $memcache
	 */
	public function setMemcache(Memcache $memcache) {
		$this->_memcache = $memcache;
	}
	
	/**
	 * Gets the memcache instance used by the cache.
	 *
	 * @return Memcache
	 */
	public function getMemcache() {
		return $this->_memcache;
	}
	
	/**
	 * {@inheritdoc}
	 */
	public function getIds() {
		$keys = array();
		$allSlabs = $this->_memcache->getExtendedStats( 'slabs' );
		
		foreach( $allSlabs as $server => $slabs ) {
			if( is_array( $slabs ) ) {
				foreach( array_keys( $slabs ) as $slabId ) {
					$dump = $this->_memcache->getExtendedStats( 'cachedump', ( int ) $slabId );
					
					if( $dump ) {
						foreach( $dump as $entries ) {
							if( $entries ) {
								$keys = array_merge( $keys, array_keys( $entries ) );
							}
						}
					}
				}
			}
		}
		return $keys;
	}
	
	/**
	 * {@inheritdoc}
	 */
	protected function _doFetch($id) {
		return $this->_memcache->get( $id );
	}
	
	/**
	 * {@inheritdoc}
	 */
	protected function _doContains($id) {
		return ( bool ) $this->_memcache->get( $id );
	}
	
	/**
	 * {@inheritdoc}
	 */
	protected function _doSave($id, $data, $lifeTime = 0) {
		return $this->_memcache->set( $id, $data, 0, ( int ) $lifeTime );
	}
	
	/**
	 * {@inheritdoc}
	 */
	protected function _doDelete($id) {
		return $this->_memcache->delete( $id );
	}
}